fix(版面)：点击内容崩溃处理

@@ -17,7 +17,7 @@ export class TrackingUtils {
   static fillPositionWith(attr: ParamType) {
     let pageName = attr["pageName"] as string
     let action = attr["action"] as string
-    if (action.length > 0) {
+    if (action != null && action.length > 0) {
       attr["saPosition"] = pageName + "_" + action
       return
     }